Fiber container manufacture



May 21, 1940; J. M. HOTHERSALL FIBER CONTAINER MANUFACTURE Filed Dec. 9,1938 2 Sheets-Sheet 1 NVENTOR ATTORNEYS y 21, 1940- J. M. HOTHERSALLFIBER CONTAINER MANUFACTURE Filed Dec. 9, 1938 2 Sheets-Sheet 2 INVENOR. 9% Z. ,rzz zy in mi m W1 \TTORNDS Patented May 21, 1940 UNITEDSTATES CONTAINER MANUFACTURE John M. Hothersall, Brooklyn, N. Y.,assignor to American Can Company, New York, N. Y., a corporation or NewJersey Application December 9, 1938, Serial No. 244,868

Claims.

The present invention relates to a method of preparing rectangular fibercontainers and has particular reference to the forming of a fibercontainer having rigid supporting truss portions 5 adjacent the ends ofthe body on which end members are disposed and held in a permanent oint.

J The invention contemplates first the forming of a truss reenforcedsection in a tubular fiber 9 body and into one or both ends of the bodyare then inserted either or bothtop and bottom end members. These arepositioned in an exact relation to the truss portions of the body so asto produce the maximum strength and rigidity for L the container whenthe adjacent body portions are shaped around the edges of the endmembers and after these are fully sealed in a permanent junction whichaccentuates the supporting truss effect.

The invention is directed to an improved process of producingrectangular fiber containers having rigid supporting truss portions suchas are embodied in the container shown in either of my two Patents2,085,979 and 2,089,958, issued re- 35 spectively on July 6, 1937, andAugust 1'7, 1937, I

and each covering Containers.

An object of the present invention is the provision of a method ofmanufacture of rectangular fiber containers which provides a tubularbody having supporting truss portions formed in the body wall adjacentone or both ends and on these supporting sections a top or bottom end orboth are firmly secured in tight adhesively- /secured joints which areof a construction to cooperate with the truss portions to provide arigid supporting truss effect at the end of the container.

Numerous other objects and advantages of the invention will be apparentas it is better understood from the following description, which, takenin connection with the accompanying drawings, discloses a preferredembodiment thereof.

Referring to the drawings:

Figure l is a perspective view of a reeniorced fiber container ofsupporting truss construction made in accordance with the steps of thepresent invention;

Fig. 2 is a perspective view-of a blank from which the container of Fig.1 may be made;

Fig. 3 is a perspective view of a partially bent blank illustrating thefirst step in the present method of manufacture; I

Fig. 4 is a perspective view of the blank of Figs. 6 and 7 areperspective views of inter- 5 mediate stages of manufacture in producingthe body of Fig. 5, these views also showing some of the principal partsof the mechanism required;

Fig. 8 is a perspective view of the tubular body after truss portionshave been partially formed 10 adjacent the two ends of the body;

Fig. 9 is a sectional, fragmentary view showing one end of such a bodywith its truss portion and also showing parts oi a beading mechanismfor. effecting this step in the process; I

Fig. 10 is a perspective view of the top end of the tubular body withits top end member in inf serted position and resting on the trusssection;

Fig. 11 is a fragmentary sectional view of the container parts shown inFig. 10 and also showing the principal element of aninsertingmechani'sm;

Fig. 12 is a view similar to Fig. 10 and showing the corners of the bodytucked-in over the top member;

Fig. 13 is a perspective view illustrating this. corner tuckingoperation;

Fig. 14 is a fragmentary sectional view of one end of the container andshowing mechanism for bending and reshaping parts of the body wall; 30

Fig. 15 is a schematic sectional view on a smaller scale of a heatingoven showing a partiailly completed container passing therethrough; an

Fig. 16 is a sectional view similar to Fig. 14 and 35 showing parts ofsqueezing mechanism for completing the truss reenforced endjoint.

The present invention is directed to a series of steps in themanufacture of rectangular fiber container and Fig. 1 illustrates by wayof exam- (.0 plc a fiber can structure which may be the result of afulfillment ofsuch method steps. The container consists primarily. of arectangular body II and bottom and top closures or end members l2andl3.i

The can body consists of four side walls I having right angled corners.One of the side walls consists of two parts which are joined together bya suitableadhesive in a side seam l5.

The bottom i2 and the top l3 each consists of 50 a disc offiber'material the edges of which are interlocked with the adjacent endof the body and held by adhesive.

A section of the can body is bent obliquely inwardly at "5 adjacent thebody end to form a 55 supporting element for the can end and this alsoproduces an inwardly inclined reenforcing truss at that part of thecontainer. This body wall is thence bent outwardly in as relativelysharp corher to provide a horizontally outwardly extending ledge I! onwhich the can end rests. This sharply bent ledge cooperates with theinwardly inclined truss portion |6 to constitute a rigid non-collapsiblestructure which resists outward and inward movement of the body wall andinsures against vertical collapse due to any longitudinal strains at theends or axially of the container.

The top or upper end closure I3 is seated upon the ledge l1 and theextreme edge of the body is then folded down at I8 to provide ahorizontally extending body part or terminal portion I9 above or outsidethe end closure. The bottom or lower end closure I2 is similarly seatedand held. An empty container having both ends closed (Fig. 1) is theresult desired from the sequence of operations of the present invention.

Such a container obviously must be opened prior to filling with itscontents and later the contents will be sealed until such time as thefilled container will be opened for dispensing of the contents. Mypatents mentioned above explain some of the uses of such acontainer.

The top member I3 is formed with a filling and discharge opening 24(Figs. 10 and 16) which is located near one corner of the top. A

fibrous auxiliary closure member 25 is also pre-- vided and is locatedexterlorly of the top closure l3. The center portion of this auxiliarymember is secured to the top in any suitable manner as by a staple 26.One end section of the auxiliary closure extends over the dischargeopening 24 of the top closure and is formed with a'drawn plug section 2!which is adapted to fit in and close the discharge opening both prior tofilling with contents and after filling up to the time of dispensing ofthe contents. The detailed steps for producing the empty container ofFig. 1 will now be given.

For the rectangular shape of Fig. 1 a rectangular body blank 3| (Fig. 2)is provided and a suitable adhesive such as a thermoplastic cement or aremoistening glue may be applied to certain desired portions of theblank. The kind oi adhesive used and the manner of application 1 formsno part of the present invention.

, short edge.

For the particular container under consideration two strips of adhesive32 will be applied along the two long edges of the blank 3| and aconnecting strip 33 will be applied along one In the present embodimentall of the cement will be on only one surface of the blank. I

To assist in subsequent bending and forming of the blank into itstubular shape crease lines 34, 35, 36 and 31 may be pressed in as shownin Fig. 2, all of these lines being parallel to the short end edges ofthe blank. The spacingandlocation of such crease lines will bedetermined by the size and shape of the desired body.

Beginning with such a blank 3| the first step of the present method isthe bending of the blank along the crease lines 35, 36 so that theU-shape of Fig. 3'results. This partially formed blank will be indicatedby the numeral 39. The bent comers are then right angle corners asshown.

This operation may be brought about by the cooperation of a formingmandrel or horn 4| (Fig.4) over which the blank is bent, and formingwings 42 which do the bending.

Such forming wings may be hinged on a shaft 43 located below the horn,the two wings being brought up simultaneously against the under side ofthe blank.

The wings 42 swing the blank walls over against the side walls of thehorn 4|, the blank being thus bent along the crease lines 35 and 36 intothe partially formed blank 39 as described. The wings 42 are shown atthe end of the bending stroke in Fig. 4 and in such position the sidewalls of the U-form of blank 39 are held tightly pressed against theside walls of the horn. The surface containing the adhesive strips 32,33 is on the inside.

Fig. 6 shows the next step in the operation at which time a furtherbending of the blank takes place, this time along the crease lines 34,31. At the same time the adhesive is rendered tacky. Where athermoplastic cement is used, hot air for example, may be projectedagainst the strip 33 as the short end of the blank is being bent over.If a remoistening glue constitutes the adhesive, water vapor, steam orthe like is projected against the strip 33 as the bending proceeds.

The U-shaped partially bent blank 39 while still on the horn 4| is movedlongitudinally thereof for this combined bending and adhesiveconditioning step. Such longitudinal movement may be performed by ablank and can body feeding device 45 (Fig. 6) actuated in a suitablemanner.

Stationary forming" plates 46, 41 are held in spaced position on eitherside of the horn 4| and as the U-shaped blank 33 advances along the hornunderthe action of the feeding device 45, the sides of the blank betweencrease lines 34, 35 and between 36, 31. pass between the plates 46,

4'! and the horn 4|. In doing this the long side of the blank 39 abovethe crease line 31, engages against an inclined edge 48 of the plate 41and as the blank continues to advance this part of the blank is moveddown as the wall bends along the crease-line. When the blank has movedunder the plate 41, this section beyond the crease line lies fiat on thetop of the horn 4|, as in Fig. 6.

Just after the long side or blank section be yond the crease line 31starts to bend down, the short side of the blank, that is the sectionbeyond or outwardly from the crease line 34, engages against an inclinededge 49 of the plate 46 and this section begins its bending at thecrease-line 34. As the blank moves into the plate 46, the short sectionis laid down over the long section of the blank already down on thehorn.

The efiect of this difference in timing for bending first along thecrease-line 31 and thence along the crease-line 34, is to leave theshort side spaced above the long side for a moment while the blankadvances between the forming plates 46, 41. While the short side is thusslightly elevated above the long side the adhesive strip 33 on the edgeof the short side passes along a nozzle 5| which is held in a stationaryposition. Hot air is projected from the-nozzle 5| and thisimpingesagainst the adhesive strip 33 and renders the same moist ortacky. By the time the blank has moved through the plates 46, 41, theedge of the short strip containing the adhesive strip 33 has beenbrought down against the long side of theblank.

If a remoistening glue is used, steam or water vapor will pass from thenozzle 6| against the pre- This body may be further advanced along thehorn and brought into a bumping station shown in Fig. 7. The overlappededges of the wall sections with the tacky adhesive 33 interposedtherebetween is now positioned under a pressure hammer 55. Hammer 55presses down upon the overlapped parts holding these parts for a momentagainst the horn. This operation takes only a moment and the tackycement quickly sets so that when the hammer 55'is raised the side seamI5 is complete.

In the next operation the ends of the tubular body 54 are subjected to abeading operation as a preliminary part of the forming of a trussportion. This preliminary action is for the purpose of obtaining theoblique body wall part 16. A head 51 (Fig. 8) is pressed into an end ofthe tubular body 54 by a heading mechanism the principal parts of whichare indicated in Fig. 9.

Each side of the body may be progressively subjected to a beadingoperation or the four sids may be beaded at the same time. To effectsuch beading a grooved anvil die BI is positioned inside of the tubularbody and a cooperating outside squeezer jaw 62 is brought down againstthe outside of the body. The squeezer Jaw 62 carries a beading ridge 63which contacts the body wall and forces inwardly the engaged part of thewall forcing it into a groove $4 formed in the die 6|.

This draws the bead 51 in the body.

Itwill be observed by reference to Fig. 9 that this bead 57 includes theledge I! which is bent at right angles at the inner line of the adhesivestrip 32 on the end of the body and on the inside,

leaving an outwardly and axially extending flange 66. This straight wallor ledge is bent outwardly in a sharp corner where it merges into theobliquely disposed truss wall 16. A beaded can body 68 (Figs. 8 and 9)is the result of these closure member 25. top member I3 is beinginserted) into the end of operations.

The next step in the instant method is the insertion of a can end memberinto the beaded end of the body 68. In Fig. 10 there is disclosed thetop member It in its position within the flanged end of the body andresting upon the ledge I! of the head 51. The insertion of the bottomend 12 is accomplished in exactly the same manner and the relativeposition of the ends, bottom and top, within the body, is the same. Fig.11 illustrates the insertion of the top end-and it will be understoodthat the bottom end is inserted in exactly the same way.

An inserting head H. having a recess 12, is moved toward the ledge l7!and carries before it a can end for the inserting operation. The recess'52 forms a clearance for the fibrous auxiliary At the time that the canthe can body (it the plug closure section 21 is partially open as itextends out at a slight angle as clearly illustrated in Fig. 11.

After a can end has been inserted into the container body 68 theextending flange 66 is tucked in at its four corners as at I3 (Fig. 12).This 1 of the can body 88 and in this movement theblades strike againstthe corners of the extending flange section Stand force down the flberstock at the corners to produce the tucked-in corners 13 and thedrawn-in flanges 14.

Fig. 14 illustrates the next operation wherein the bead 51 is engaged byan anvil die member 11 and while so engaged the drawn or necked-inflange parts ll are struck by a pressure head member 18. This is shownas applied to one side of the can end but it will be understood that allsides of the end are operated on. This forces the drawn-in flange partsdown against the inserted top end, the adhesive strip 32 beinginterposed between the outer surface of the top end and the inside ofthe flange part 14. This is only a momentary pressing and creasingaction and after the parts 11, "I8 are removed from the can, the flangesection 14 springs back as illustrated in the lower part of the bodyshown in Fig. 14.

The adhesive 32 on the inside of the inclined flanges I4 is next heatedto render. the adhesive tacky. As exemplary of this step Fig. 15 showsthe body 68 with its inserted ends passing through a heating chamber BIwhich may be enclosed within a housing 82. The bodies may beconveniently carried through the chamber on a belt 88, passing in by wayof an entrance opening I. After heating, the containers pass out througha discharge or exit opening 85. Obviously the adhesive 32 could beheated locally but in any event the result of this operation is to makethe adhesive sections 32 tacky.

The final operation upon the can body to completely form the reenforcingtruss sections ll and close the end joints of the body is graphicallyillustrated in Fig. 16, where one side of the container is being sealed.It will be understood that all sides are likewise treated to form thecompleted container.

An anvil die member BI is used to back up the parts and for this purposea projecting tapered edge of the member is inserted within the groove51. This member 9| is preferably cooled as by circulation of a coolingmedium through a. channel 92 formed in the member, circulation beingobtained by means of pipes in any well known manner. Cold water providesa convenient cooling medium for this purpose.

It will, be observed by comparing Figs. 14 and 16 that the coolingmember 9| assumes the same position as that formerly occupied by theanvil 11 in a preceding operation. A clinching and sealing pressure head95 is now used in cooperation with the anvil 91 to again press down theflange parts M. This time since the adhesive in the strip 32 is in atacky condition, the flange parts when pressed down against the top ofthe container remain in that position, sticking or adhesively securingthe parts fast together.

The pressure head 9-5 assumes the same position as that formerlyoccupied by the head 18 (Fig. 14) but in the case of the head it ismaintained cool by circulation of a suitable cooling medium withinthehead.

For this purpose the head is formed with a chamber 96 through whichwater or other cooling medium may be circulated by way of pipes 91. Atthe time, therefore, of the flnal pressing of the body flange down onthe edge of the end member the adhesive is immediately set by thesecooled operating parts. A final sealed joint is the result, thisproviding the inclined truss portion l8, its supporting ledge l1, andthe folded the body l8, as previously described in connection with Fig.1.

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and it will beapparent that various changes may be made in the steps of the processdescribed and their order of accomplishment without departing from thespirit and scope of the invention or sacrificing all of its materialadvantages, the process hereinbefore described being merely a preferredembodiment thereofr I claim:

1. The method of preparing fiber containers which comprises shaping afiber blank having cement edge strips on one surface into a tubular canbody with said cement strips-on the inside, forming a side seam on saidbody by treating an intermediate cement strip between overlapping edgesof the blank and by pressing said edgestogether, inwardly beading an endof said can body to produce inwardly extending rigid supporting trussportions adjacent said cement strip edges each merging into anintermediate outwardly extending ledge portion terminating in an axiallyextending flange, inserting a flat can end into the beaded end of saidbody and against said ledge portions, and forming an end seam betweenthe can body and said can end by first treating said interposed cementstrips and then folding inwardly and tightly squeezing said axiallyextending flanges over the outer periphery of said seated flat can endto lie flat thereagainst while setting said interposed cement to providea container having its body wall braced against inward and outwardmovement,

2. The method of preparing rectangular fiber containers which comprisesbending a fiber blank having thermoplastic cement edge strips on onesurface into a tubular can body with said cement strips on the inside,saidbody being square in cross section, forming a side seam on said bodyby heating an intermediate cement strip between overlapping edges of theblank and by pressing said edges together, inwardly beading both ends ofsaid can body to produce inwardly extending rigid supporting trussportions v adjacent said cement strip edges, each truss portion merginginto an intermediate outwardly extending ledge portion terminating in anaxially extending flange, inserting flat square can ends into said bodyand against said truss and ledge portions, and forming end seams betweenthe can body and can ends by first, heating said interposed cementstrips and then folding inwardly and tightly squeezing said axiallyextending flanges over the, outer periphery of each seated flat can endto lie flat thereagainst while setting said interposed cement to bracethe body wallagainst inward and outward movement.

3. The method of preparing rectangular fiber containers which comprisesproviding a fiber blank having thermoplastic cement strips on a surfacethereof adjacent certain of its edges, bending said blank into U -shapewith two square corners and with said cement strips on the inside,

further bending the legs of said U-shape blank into two right angledcorners the while bringing the ends of said blank into overlappingspaced relation with a cement strip therebetween, heating saidinterposed cement strip to render it tacky, pressing together saidoverlapped blank ends in a side seam thereby producing a tubular canbody with cement strips extending along an end thereof, beading inwardlythe end of said body flanges to render it tacky, and sealing said endmember in said body by folding inwardly and squeezing said flangestightly against the r interposed edges of said flat end member to lieflat thereagainst, said truss portions reenforc ing the body wallagainstinward and outward movement.

4. The method of preparing rectangular fiber containers which comprisesproviding a fiber blank having thermoplastic cement strips on a,

surface thereof adjacent its two longitudinal edges and one of itstransverse edges, bending said blank into U-shape with two squarecorners and with said cement strips on the inside, further bending thelegs of said U-shape blank into two right angled corners the whilebringing the ends of said blank into overlapping spaced relation withits transverse cement strip therebetween, heating said interposed cementstrip to render it tacky, pressing together said overlapped blank endsin a side seam thereby producing a tubular can body with itslongitudinal cement strips extending along both ends thereof, beadinginwardly the ends of said body adjacent said cement strips to producerigid supporting truss portions merging into intermediate outwardlyextending ledge portions terminating in axially extending flangeportions and leaving cement lined areas at the ends of said flangeportions, inserting flat end members inside of said flanges and seatingthe-same on said beaded truss and ledgeportions, heating the cement onsaid body end flange portions to render the same tacky, and sealing saidend members in said body by folding inwardly and tightly squeezing saidflange portions against the interposed peripheral edges of said end flatmembers to lie flat thereagainst and to cooperate with said trussportions to brace the body wall against inward and outward movement.

5. The method of preparing rectangular fiber containers which comprisesproviding a fiber blank having thermoplastic cement strips on a surfacethereof adjacent its two longitudinal edges and one of its transverseedges and also having crease lines extending transversely of the blank,bending said blank into U-shape along two of its crease lines with itscement strips inside, further bending the blankalong other crease linesand into substantially tubular form but with the transverse cement stripedge slightly separated from, the uncemented transverse edge, heatingsaid transverse cement strip to render it tacky, squeezing the open.edges together while the cement sets to form a tubular container bodyand with the longitudinal cement strips extending around the inside ofthe ends of said flange portions, inserting flat container ends in saidbeaded tubular body and seatingthe same against said truss and ledgeportions, tucking-in the corners of the body by pressing the cornersagainst the by pressing thesaid creased flange portions against the saidflat ends with the tacky cement therebetween the while cooling thepressed parts to quickly set said cement and to complete the forming ofa fiber container having its body wall 5 braced against inward andoutward movement.

JOHN M. HOTHERSALL.

